Dental-engine hand-piece



(Model.) 2 Sheets-Sheet 2.

C. P. GROU'I.

DENTAL ENGINE HAND P IEGE.

'INVENTOR UNITED dSTATES CHARLES P. GROUT, OF NEW YORK, N. Y., ASSIGNOB'lO JAMES W. WHITE J. CLARENCE "WHITE, AND H. M. LEWIS, TRUSTEES, OFPHILADELPHIA PENNSYLVANIA PATENT Cri-iron.

DENTAL-ENGINE HAND-PIECE.

SPECIFICATION forming part of Letters Patent No. 277,126, dated May 8,1883.

Application tiled May 24, 1880.

To all whom it may concern:

Be it known that I, CHARLES P. GaoUfr, a citizen of the United States,residing in the city, county, and State of New York, have in- 5 ventedcertain new and useful Improvements in Dental-Engine Hand-PieceAttachments and Operating-Tools, of which the following is aspecification.

My invention relates more especially to den- Io tal-engines of the classhaving a spindle-chuck or tool-holder rotated iu bearings in a handpiececasing by means ot' a iiexible driving-connection, which permits thehand-piece grasped by the ngers of the operator to be moved I5 freelyabout in various directions to permit the operating-tool driven by thespindle-chuck to be applied at the point desired. The best types of thisclass of engines, in my opinion, are those which have been long made andsold zo under the name ot' the S. S. White Dental Engine, some of thelater forms of which are shown in Letters Patent No. 219,320 and N o.222,093, dated, respectively, September 2 and November 25, 1879.

25 'lhe object of the irst part ot' my invention is to provide auimproved angle attachment for dental-engine hand-pieces or atool-carrier having the capacity of adjustment so that theoperating-tool carried by said attachment or 3o carrier may be readilyplaced at different angles to the longitudinal axis ot' the hand-piececasing, or to the driving-shank of said carrier or attachment, so as tooperate upon any part ot' a tooth, the adjustment of the angle at which3 5 the operating-tool of the attachment or carrier operates beingaccomplished easily, rapidly, and with nicety, while the tool, when soadjusted, is securely locked against accidental variance.

4o I am of course aware that angle attachments or tool-carriers havingthe capacity of adjustment to vary the, angle of the operating-tool arevery common.

The object of the next part of my invention 45 is to provide improvedmeans whereby atoolshank may be easily and rmly locked in its rotarytool holder or chuck againstany wabbling or lateralmovement, whichmovement, when not overcome, is a serious obstacle to 5o the skillfulperformance of the necessarily deli- (Modei.) Y

cate operations required by the tool in working upon natural teeth inthe mouth.

rlhe subject-matter claimed will be specifically pointed out at the endot the specification. 55

In the accompanying drawings, which illustrate the best way now known tome of embodying my improvements, Figure l is a side view, partly insection, o t the improved angle attachment or carrier. Fig. 2 is alongi- 6o tudinal section therethrough, showing themanner of locking thetool in the socket of the tool-holder ot' said attachment. Figs. 3, 4,and 5 are transverse sectional views through the attachment or carrieron the lines 3, 4.-, and 5, 6; respectively, of Fig. 2. Fig. 6 is asectional view on the line 6 of said Fig. 2. Fig. 7 is a view ofahand-piece with an operating-tool secured in the spindle tool-holderthereofaccording to my invention. Fig. S is a longitudinal 7e sectionthrough the front end of the hand-piece, to show more clearly the mannerot' locking the tool-shank against lateral or shaking motion in thetool-holder; and Fig. 9 is a view in perspective of the device whichlocks the tool- 75, shank in the holder against the aforesaid lateralmovements.

I will irst describe the angle attachment shown in Figs. l to 6,inclusive.

The barrel or tube A of the attachment or 8o carrier is of the usualform, so as to fit or be slipped upon the end of the hand-piece casingand be retained thereon, as usual, while the driving-sh ank B, fitted inbearings at the front end of said barrel, enters the socket in the 8:front end of the rotary spindle-chuck or toolholder of the hand-piece inthe usual way, so as to be locked in said chuck and be given a rapidrevolving motion, which is communicated to the tool-holder oftheattachment by gear- 9o ing, as will be presently explained. Connectedwith the front end ot' the barrel A-by screwthreads in this'example-isan annulus orring,

C, screwed upon and made fast byaconnectingscrew, c, to a tubularsection, I), of the car- 9 5 `rier, which section D is provided withears or projections d d at its front end, between and to which ears d dthe casing-E, which affords bearings for the tool-holder F of theattach- A ment, is pivoted, so that said casing E may ioo ffl swing orbe rocked on said pivots to vary its angle and that of the tool-holderF, nwhich the operating-tool is inserted relatively to the axial line ofthe hand-piece casing and to the driving-shank B and barrel A of theattachment. The said shank B is locked from endwise movement in thetubular section D, while free to revolve axially therein, by means of anannular shoulder, b, of said sh ank, which abnts against the rear end ofa tubular bushing or sleeve, Gr, locked in the socket of the section I),and surrounding a reduced portion of the shank, the gear-wheel H at thefront end of said shank B affording an annular shoulder, h, to abutagainst the front end of said sleeve or bushing G, all of which isclearly shown in the sectional view, Fig. 2. The bushing or sleeve G,which constitutes the bearing in which the shank B turns, is secured inthe socket of the tubular section D by means of a fasteningscrew, d; butthe said bushing may be otherwise connected with the section D orsecured in the socket thereof. By means of the fastening screw d inY theorganization shown I am Aenabled to shift'the sleeve or bushing tocompensate for wear. The said toothed gear-wheel H at the front end ofthe shank B is of well-known construction, and meshes with a spnrwheel,I, also of wellknown construction, mounted on the rear or butt end ofthe tool-holder F of the attachment, so as to give said tool-holder arapid revolving motion. The said tool-holder F is conical or tapering atits front end to it a corresponding seat or bearing, e, formed at thefront of the rocking casing E, while its buttend is provided with aconical socket, f, for the reception of the cone-shaped or tapering endofa set-scre\ v, J, passing` through the butten`d of the said casing E,whereby the said screw forms the rear bearing on which the tool-holderturns, so as to enable said holder to rnn steadily when driven by thegearing. Said conical end bearing is adjustable by its screw-threads, itwill be observed, so that it can be screwed up or tightened, and thuscompensate for and take up wear of the tool-holder in or upon itsbearings, and thereby enable it to run smoothly and steadily at alltimes. The said toothed wheels H and I are so itted as to remain ingear, whatever may be the angle of the casing E and tool-holder Frelatively to the main body or barrel A of the attachment, by theadjustment or rocking of the said casing upon its pivots.

In order to vary the angle of inclination of the casing E, and with itthe tool-holder F and the operating-tool driven thereby, I connect aVcurved plate, K, fitted to the reduced side of the tubular section D,soas to slide endwise thereon, with the pivoted or jointed casing E bymeans of links l l, one on each side, whereby by the endwise adjustmentof the sliding plate Kv the angle of the casing E and tool-holder F,will be varied, as is obvious, the sliding of the plate inwardlyincreasing the angle by drawing the outer end of the casing toward thebody of the attachment, while forcing it outwardly lessens the anglerelatively to the axialline of the hand-piece and barrel of theattachment by carrying the outer end of said casing away from the bodyof the attachment. The reciprocation orA sliding movement of theplateKis accomplished with great nicety and firmness, and at the sametime with ease and rapidity, by a turning tin,

ger-ring or thimble, L, mounted upon the reduced portion of the tubularsection D, between the shoulder d2 thereof and the annulus or ring C, aninternal screw-thread of said finger-ring L fitting corresponding malethreads on the curved surface of the sliding plate K, whereby, as thelinger-ring or thimble L cannot move endwise, owing to its being seatedbetween shoulders upon each side, it will be obvious that any motiongiven to the ring around the section D will move the sliding plate Kendwise, thereby, owing to the link connection with the casing E,determining the angle of said easing, as before described.

I will now describe the manner of inserting and securing theoperating-tool in the socket ofthe tool-holder. The said tool Ml isprovided with atapering shank, as clearly shown in Figs. l, 2, 7, and 8,and upon this tapering portion of the shank is fitteda sliding tubularsplit wedge, m, the said sliding wedge being tted upon the tool-shank inany of the well-known ways common in the art, so as preferably to be apart of the tool, while capable of moving endivise to a limited extentupon the inclined portion of said shank. The tool-shank is inserted inthe socket of the holder, as shown in Figs. 1 and 2, (which form ofholder has no device to lock the shank in the socket,) and the tubularwedge then Amoved endwise ou said shank into the mouth of said socket,the wedge expanding as it is forced up the incline of the toolshankuntil it completely fills the socket, thereby locking the tool in thetool-holder not only as against endwise movement, but also against anylateral play or wabbling move` ment, whereby the tool is driven asfirmly and steadily as the holder itself, of which, when the wed ge isforced home, it virtually forms a part. An enlargement or collar, m', atthe outer end of the sliding wedge M constitutes the means of forcing itup the inclined surface of the toolshank and for withdrawing it when thetool is to be removed from the socketof the tool-holder.

In Fig. 9 of the drawings I have shown the tubular split wedge inperspective detached from the tool, while in Figs. 7 and 8 I have showna tool having the wedge applied tted in the socket of the spindle-chuckof a dentalengine hand-piece, which chuck is provided with tool-lockingdevices, operated in any of the well-known ways, to secure or lock thevtool-shank therein, the tubular wedge lVI merely serving to ll up thesocket and prevent any lateral motion between the tool-holder and tool,

IIO

which motion, unless overcome by a eonipeu sating device, is veryobjectionable.

It will of course be understood that any wear or enlargement of thesocket of the tool-holder is compensated for by the Wedge.

I claim as my invention- 1. The combination, substantially ashereinbefore set forth, of the barrel or tube, the driving-shank, thepivoted casing carrying the rotary tool-holder, the slide, alink-connection between said casing and slide, and a turning screw-ringto move said slide to vary the angle of the tool-holder relatively tothe axial line of the barrel of the attachment.

2. The combination, substantially as hereinbefore set forth, of thetool-holder casing, the toolholder mounted in said casing, having acone-journal at its front end and acone-socket at its butt-end, and thetapering set-screw passing through the rear end of said casing into saidconesocket of the tool-holder, Whereby the tool-holder is provided withcone-bearings and compensation for Wear permitted by means of a singleset-screw.

3. The combination, substantially as hereinbefore set forth, of thetapered-shank operat ing-tool with the endwise-movable tubular,

split wedge encircling said shank, and proz5 GHAS. P. GROUT. Witnesses:

SAML. V. BILLINGS, FRANCIS C. HARMSTAD.

